Clamp for concrete-forms.



F. G. & H. 0. McMILLAN.

CLAMPFOR CONCRETE FORMS.

APPLICATION FILED APR. I9. I9I6.

Patented Feb. 20, 1917.

JWV/ pf w/E/e AWOENEYS FRANK G. MCMILLAN AND HOWARD O. MGMILLAN, OF MINNEAPOLIS, MINNESOTA.

CLAMP FOR CONCRETE-FORMS.

Application filed April 19, 1916.

'1 0 all whom it may concern:

Be it known that we, FRANK G. MOMIL- LAN and HOWARD O. MoMILLAn, citizens of the United States, residing at Minneapolis, in the county of Hennepin and State of Minnesota, have invented certain new and useful Improvements in Clamps for Concrete-Forms; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

Our invention has for its object to provide an extremely simple and highly eflicient clamp for concrete forms, and to such ends, generally stated, the invention consists of the novel devices and combinations of devices hereinafter described and defined in the claims.

Particularly, the invention relates to clamps wherein a wire is employed as a tension member and the tightening of the clamp is produced by coiling of the wire on a spindle or rotary shaft. In a clamp of this character, it is of the utmost importance that after the wires are coiled on the spindle and it is desired to release the clamp, this may be done simply by driving the coiled portion of the wire off from the ends of the tightening spindle. Simple and efficient means should also be provided for securing the spindle in different rotary positions so that it may be locked in whatever position it may be when the wire is drawn to the proper tension. These objects we accomplish in our present invention, the preferred form of which is illustrated in the accompanying drawings wherein like char acters indicate like parts throughout the several views.

Referring to the drawings:

Figure 1 is a perspective view showing the improved clamp applied to laterally spaced posts of a form such as used in constructing concrete walls;

Fig. 2 is a section taken approximately in the vertical plane indicated by the dotted lines w aa on Fig. 1;

Fig. 3 is a plan view of the spindle and lock key; and

Fig. 4 is an end view of the spindle.

Although the clamp is, in the drawings,-

shown as applied to a wall form, it is, of course, understood that it may be employed in connection with various different forms,

Specification of Letters Patent.

Patented Feb. 20, 1917.

Serial No. 92,286.

such, for example, as forms for the construction of concrete columns.

Of the parts of the form illustrated, the numeral 1 indicates the posts or uprights, the numeral 2, the temporary wall boards, and the numeral 3 a spacing strut placed between the upper portions of the laterally spaced boards 2 in line with the posts 1 and above the concrete 2 The tension wire is indicated bythe numeral 4 and this is shown as bent around one of the posts and its ends are brought across the top of the form and past the sides of the opposite posts where they are attached. to the tightening spindle. This tightening spindle 5 is an iron or steel shaft, the ends of which are pronged or formed with open wire receiving notches 6. In its body, the spindle is formed with elongated dia metrical slots 7 there being preferably two, located the one at right angles to the other, but offset longitudinally of the spindle. The numeral 8 indicates an angular lock key, one arm of which is preferably longer than the other. When the clamp is applied, the ends of the wire or ends of the wires, where two are employed) are placed in the notches 6, or between the end prongs of the spindle and the spindle is then rotated so as to twist the wire around the pronged ends of the spindle.

One of the keys 8 may be used as a lever for rotating the spindle, or, if preferred, a longer and more powerful lever may be employed for that purpose. At any rate, when the clamp is drawn to the proper tension, the key will be inserted in one of the slots 7 and engaged with the adjacent post 1 to lock the spindle with the wire under the desired tension. The key may be applied in either of the slots 7, and, furthermore, may be applied with either its long or short arm in the selected slot, and with its other arm turned either away from the post, as shown in Figs. 1 and 2, or with the said projected arm turned into engagement with the post. This makes it possible to lock the spindle in any one of about sixteen different positions, so that, when the wire is once drawn under the proper tension, it need not be given any appreciable slack in applying the key.

After the concrete is set and it is desired to remove the form, it is only necessary to drive the coiled ends laterally off from the pronged ends of the spindle. This, however,

would preferably be done after first removing the key and releasing the spindle and Wires from tension.

The device described is not only of very small cost, but may be very quickly and easily applied, as well as very quickly and easily removed. In actual practice, it has been found highly satisfactory, convenient and efficient as a clamp of the character described.

IV hat we claim is:

1. In a clamp of the kind described, a spindle having an exposed intern'iediate portion capable of being directly rolled against a support, perforated at its intermediate por tion to form key seats and. provided with pronged ends upon which the ends of a wire may be simultaneously wound and from which the wound coils are adapted to be removed laterally in combination with a key insertible into said key seats to lock said spindle against the tension of the stretched wire.

2. In a clamp of the kind described, a spindle having pronged ends adapted to receive and coil the ends of a tension wire, said spindle having in its body diametrical slots at an angle to each other, and an angular key insertible into either of the slots of said spindle with its projecting arm turned either toward or from the post or body en gaged by said spindle.

3. A clamp of the kind described com prising a spindle having pronged ends adapted to receive and coil the ends of a tension wire and having in its body diametrieal slots at an angle to each other, and. an'angular key having relatively long and short arms, either of which is insertil'ile into either of the slots of said spindle with the other arm turned either toward or from the post or body engaged by said spindle.

In testimony whereof we aliix our signatures in presence of two witnesses.

FRANK G. MOMILLAN. HOWARD O. MOMILLAN.

Witnesses:

BERNIGE G. VHEELER, HARRY D. KILGORE.

Copies of this patent may'be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

